Clamp for coupling pile shell to mandrel



Marth 14, 1967 c. GUILD 3,308,627

CLAMP FOR COUPLING PILE SHELL TO MANDREL Filed March 8, 1963 F|G.| Z2 I 22 IN V EN T 0R.

CHARLES L. GUILD 32 y ATTORNEYS United States Patent ware Filed Mar. 8, 1963, Ser. No. 263,985 2 Claims. (Cl. 6153.7)

This invention relates generally to pile driving and the use of mandrels and pile shells and is particularly adapted to sonic pile driving as described in United States Letters Patent No. 2,975,846, although it is not to be construed as being limited thereto.

In the use of a sonic pile driver where it is necessary to couple a generator of sonic vibrations to the pile to be driven so as to set up longitudinal sonic wave action in the pile, the need for improved methods of coupling the pile to the oscillator from a mechanical standpoint has been demonstrated. According to the invention, I have provided a coupling means between a mandrel and a pile shell which is improved with regard to flexibility and accommodation to movement of the pile during driving, such as twisting thereof. Specifically, the clamp incorporates a rigid coupling to the mandrel and a bearing coupling between this clamp and the pile shell.

In the accompanying drawings:

FIG. 1 is an elevational view partly in section of the clamp made in accordance with the invention;

FIG. 2 is an enlarged partial sectional view showing the arrangement for coupling the pile shell to the clamp;

FIG. 3 is an enlarged sectional view taken on lines 33 of FIG. 1; and

FIG. 4 is a sectional view taken on lines 4 4 of FIG. 3 of reduced scale.

In the preferred form of the invention, the mandrel is a cylindrical mandrel or a pipe section and is used in conjunction with a cylindrical pile shell or casing which may be made of corrugated sheet iron with watertight welded seams. This particular type of pile shell is well known in the art and basically consists of corrugations which run helically down the whole length of the pile shell with the bottom end of the shell closed by a boot which may be formed of sheet steel and may be Welded watertight to the shell. It should be understood, however, that other types of mandrels and pile shells may be used in accordance with the invention.

Referring now more particularly to the drawings, the mandrel 10, which is disclosed as being of the cylindrical type, is aflixed in a manner not important here to the driving head of a pile driver (not shown) which may be of the sonic type disclosed in the referenced patent. A collar 11 surrounds this mandrel, the collar being made up of two semi-circular sections consisting of portions 12 and 13. The ends of each section are formed with an enlarged boss area as at 14 and 15, respectively, which boss areas are suitably bored for the reception of tie bolts which are generally designated 16. The inner surface of each of the semi-circular sections 12 and 13 is provided with clamping pads 17 and 18, respectively, which form spot engagement to the mandrel around the periphery thereof and at a number of longitudinal locations so that a fairly even grip is provided throughout the interior surface of clamp 11. The lower portion of each section is provided with an outwardly turned flange 20 and 21, which flange is an integral part of the semi-circular sections 12 and 13. Each of the respective flanges 20 and 21 is provided with a number of apertures through which bolts 22 may extend and which couple the clamp portion to a coup-ling section generally designated 25.

The coupling section 25 is shown in greater detail in the enlarged cross sectional View of FIG. 2. Referring now to FIG. 2, it will be seen that this coupling section 25 consists of an outer cylindrical ring 26 having a flange 27 at the upper portion thereof. The coupling section also has an inner cylindrical ring 30 with a lower flange as at 31 and a depending tapered conical end piece 32. Between the inner and outer ring, a roller type bearing 37 is provided with one race coupled to each ring and which need not be described in detail by itself, and holding this bearing in place between the inner and outer rings is a Belleville washer 39. In turn to hold the washer 39 in place is an L section 33 secured to the flange 27 by screws 36. To keep foreign matter from the bearing, a seal 29 of suitable form is received in recess 28 and on flange 31, and the L section at 34 forms a seat for another seal 35 that abuts against the inner shell 30. The arrangement, accordingly, is such that the inner ring member 30 will be adapted to rotate relative to the outer ring member 26, it being remembered that the outer ring member 26 is by virtue of its coupling bolts 22 connected to the flange 20 and effectively, therefore, is maintained rigid with respect to the mandrel 10.

As illustrated in FIG. 1, a pile shell 40 is slid onto the tapered section 32 and will be held in position by friction or, if desired, a ring clamp may be used to insure coupling. With the mandrel 10 and the pile shell 40, a complete unit for driving is provided, it being only necessary to couple the mandrel to a driving means. Since in practice assembly of the clamp may be accomplished with the mandrel lying on the ground, lifting eyes 42 are provided integral with the collar 11 permitting the mandrel and/or pile shell to be positioned in place below the driving means in a set of pile driver leads. It will be apparent that during driving should the pile shell desire to rotate, the inner section 30 will rotate with the shell, and undue rotational stress that could develop by rigid coupling of the pile shell to the mandrel is avoided.

I claim:

1. A clamp coupling between a pile she-ll and a mandrel comprising:

a mandrel telescoped within a pile shell;

a collar rigidly secured to said mandrel, said collar comprising two semi-circular sections, the inner surface of each section having a plurality of pads for gripping said mandrel;

a cylindrical ring member secured to the pile shell; and

coupling and bearing means between said collar and said ring member permitting relative rotation therebetween.

2. A clamp coupling between a pile shell and a mandrel comprising:

a mandrel telescoped within a pile shell;

a collar rigidly secured to said mandrel;

a cylindrical first ring member secured within the end of the pile shell;

a second ring member aflixed to said collar and encircling said first ring member; and

3 4 coupling means between said first and second ring References Cited by the Examiner members permitting relative rotation therebetween, UNITED STATES PATENTS said coupling means comprising bearing means hav- 1,998,643 4/1935 10mm, ing first and second race members, said first race 5 2,356,351 8/1944 Phillips 235 27 member being connected to said first ring member and said second race member being connected to said CARL Q Primary Examine!- Second ling member- A. V. KUNDRAT, Assistam Examiner. 

1. A CLAMP COUPLING BETWEEN A PILE SHELL AND A MANDREL COMPRISING: A MANDREL TELESCOPED WITHIN A PILE SHELL; A COLLAR RIGIDLY SECURED TO SAID MANDREL, SAID COLLAR COMPRISING TWO SEMI-CIRCULAR SECTIONS, THE INNER SURFACE OF EACH SECTION HAVING A PLURALITY OF PADS FOR GRIPPING SAID MANDREL; A CYLINDRICAL RING MEMBER SECURED TO THE PILE SHELL; AND COUPLING AND BEARING MEANS BETWEEN SAID COLLAR AND SAID RING MEMBER PERMITTING RELATIVE ROTATION THEREBETWEEN. 